Sherline drive belt is used on both the Lathe and Mill. The one that comes with your machine should last a long time. If, however, you do need a replacement, we have them available. There is no maintenance required of the belt other than making sure it is properly tensioned. A loose, slipping belt will wear out prematurely as will one that is stretched too tight. Proper tension is just tight enough so that it does not slip under normal load. This will not only assure a long belt life, it will also have the additional advantage of providing a safety margin by allowing the belt to slip if a tool should jam in a part or an accident occur. The pulleys should also be aligned so the belt runs straight from one to the other. 40040 Sherline Standard Drive Belt Instructions